Using earth observation data to evaluate the performance of a land surface model at high northern latitudes
Clark, D.B.; Blyth, E.; Ellis, R.; George, C.; Hayman, G.; Bartsch, A.; Paulik, C.. 2012 Using earth observation data to evaluate the performance of a land surface model at high northern latitudes. [Poster] In: Planet Under Pressure, London, 26-29 March 2012. (Unpublished)Before downloading, please read NORA policies.
Recent decades have seen large changes in the environment of high northern latitude land areas, including warming and changes in snow and vegetation cover, and these are the subject of research using increasingly sophisticated models. There is a need to evaluate the models against observational data, both to quantify the performance of the current models and to guide future developments. Although data from field campaigns are an important resource, Earth Observation (EO) products are increasingly being used as the only practicable means for evaluation at the large spatial scales over which models are routinely applied. The Joint UK Land Environment Simulator (JULES) is a process-based model that simulates the fluxes of carbon, water, energy and momentum between the land surface and the atmosphere. JULES includes parameterisations of cold season processes, including a multi-layer model of the snow pack and soil freezing and thawing processes. In this paper we compare simulations of the Northern Hemisphere using JULES to a range of EO products. The EO products monitor snow cover (e.g. from ESA DUE GlobSnow, MODIS), snow water equivalent (e.g. GlobSnow), surface state (frozen/unfrozen/melting, from ESA STSE ALANIS-Methane/DUE Permafrost) and surface temperature (e.g. AATSR, MODIS). Uncertainty in the EO products arises in part because these products themselves involve models of radiative transfer processes. By comparing several quantities from a range of products we develop a consistent picture of the performance of JULES over large areas, and get a qualitative estimate of EO uncertainty. We also investigate uncertainty in the outputs from JULES that arises from uncertainties in the parameterisations and in the input data (e.g. meteorology). We propose to incorporate EO products that describe snow and frozen ground into the routine benchmarking of JULES and other land surface models.
|Item Type:||Publication - Conference Item (Poster)|
|Programmes:||CEH Topics & Objectives 2009 - 2012 > Biogeochemistry > BGC Topic 2 - Biogeochemistry and Climate System Processes > BGC - 2.2 - Measure and model surface atmosphere exchanges of energy ...|
|NORA Subject Terms:||Hydrology|
|Date made live:||03 Apr 2012 11:16|
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